Federal regulations require that obstructions to aircraft, such as towers and the like be fitted with elements to render them highly visible to approaching aircraft. For this purpose, lighting systems are deployed on structures above a certain height in localities where aircraft are present. A typical lighting system for such a purpose often incorporates a series of lights such as a beacon on top of the structure, and dual obstruction lighting (DOL) and/or single obstruction lighting (SOL) at designated heights, to provide sufficient light to be suitably visible to aircraft.
With the use of such lighting systems, there have been growing concerns of light pollution to observers on the ground within the vicinity of a tower, particularly at night. This issue becomes more problematic as the number of towers increases in residential or cottage areas.
Current solutions known in the field to control nuisance light from tower obstruction lighting includes use of light deflectors or optical stops to block or reduce light in undesired directions. By way of one example, an assembly shield has been provided including a number of frustoconically shaped elements stacked vertically where each frustoconically shaped element is spaced apart from an adjacent element to provide vertical spacing.
Some problems with the conventional tower lighting solutions are that they are prone to collecting snow and ice, and thus impeding the light.
There is therefore a need for an improved tower light shield or deflector.